African American (AA) men have a higher incidence of prostate cancer (PCa) than any other racial or ethnic group throughout the world, yet are underrepresented in exercise intervention studies. Androgen deprivation therapy (ADT) is the most commonly used hormone treatment for prostate cancer. Although this treatment has been shown to slow the growth of existing tumors, the associated suppression of testosterone leads to muscle atrophy, loss of strength, fatigue, bone loss, increased fat deposition, and functional declines that lead to a deterioration in quality of life. Strength training (ST) is now considered the intervention of choice to improve muscle size and strength and reverse the functional declines associated with these changes. For this reason, it would seem logical that ST would be an ideal intervention against the adverse consequences of ADT commonly used to treat PCa. We propose two parallel studies to address the effectiveness of ST as an intervention for improving quality of life in AA PCa patients on ADT. These studies will address the effectiveness of ST as an intervention for improving quality of life in AA PCa patients on ADT. Study 1 will consist of 10 weeks of single leg ST in which the untrained leg will serve as an internal control. This study will consist of 30 AA men with PCa between the ages of 50 and 74 who will undergo assessments of leg muscle mass, strength, fatigue, power and cross-sectional area of intermuscular fat before and after the ST intervention. Study 2 will consist of 12 weeks of whole-body ST of all major muscle groups. This study will consist of 45 additional volunteers who will undergo assessments of total body composition (fat, muscle and bone density), muscle strength, blood proteins important to PCa, fatigue perception, activities of daily living, and quality of life measures before and after the ST program. In addition, the effects of both studies on belief that volunteers will continue to participate in ST (self-efficacy) will be tested. Thus, these two studies will allow us to provide important and novel information about the efficacy of ST on improving function and quality of life in AA PCa patients on ADT, as well as the self-efficacy of patients to continue participation in a ST program. Specific Aims: The specific aims are to measure the impact of a high-quality ST intervention program on muscle size, muscle function, muscle and fat composition, muscle fatigue, fatigue perception, blood proteins associated with PCa, quality of life, willingness to continue to ST and ability to perform activities of daily living (ADL) in AA PCa patients with ADT. The proposed aim will be achieved using two complementary, but separate studies performed in parallel. Our global hypothesis is that ST is an ideal intervention for counteracting or reversing many of the unintended adverse consequences of ADT therapy in PCa patients. Our specific hypothesis is that ST will result in improvements in body composition, muscle function, functional abilities, and quality of life indicators, and that those who make the most improvements in these measures will tend to have the highest self-efficacy scores.7.